Well, is it you, or is it your situation? Or a combination of both factor? And if it's you, it could well be a part of your personality you haven't considered, such as how confident you are, and your associated body language.
You say you work: are there many women, there? What else do you do? Clubbing? Any clubs to which you belong? Do you socialise with many mates? Have you any female friends? You don't seem to have mentioned much, and, going by what I've found to be the most common 'profile' of someone your age without any relationship experience, I'd suspect that, perhaps, you are shy, and don't have too many friends, and hence you don't do too much, besides work; tell us a bit more.
In the absence of further information, as regards physical factors, I'd suggest that there are certain measure a guy can do to improve his image in the eyes of women: if you're overweight, lose weight; if you're skinny, eat a bit more and consider joining a gym; perhaps consider changing your hairstyle; adhere to certain fashions, as regards clothing; try to smile more. These may seem shallow, but such is life, alas.
Mentally, well, a lot of it boils down to confidence; women love confidence (and I'm not very confident, when it comes to approaching women, so it depresses me, this fact). Confidence can't be gotten out of nowhere, but there's a saying "you gotta fake it, to make it". Perhaps consider your body language: as I say, smile frequently, make eye contact with people, keep your head up. Generally, just try to be outgoing; make conversation, add bits to other people's conversations. I'm no Psychology student, and I've felt dubious about all this before, but, through experience, I'm beginning to think that seemingly small things such as these may make significant a difference.
I'm not quite in your situation (but I've known of many in worse a situation, if it helps to hear this), but I don't find it very easy to forge relationships with women (a contender for the understatement of the year, that), and was, myself, quite late having my first relationship; makes it all the lovelier when you do, though, trust me.
A lot of the above may not be applicable to you, so it'd be helpful if you could say a bit more about yourself in your situation. I'd imagine that, as many people would in your situation, you were being a bit hard on yourself, as regards your looks; it may seem like the obvious explanation, but there's usually more to it than that.
All the best.